These methods give reliable results for ages of the order 10 7 —10 9 years. The above equation makes use of information on the composition of parent and daughter isotopes at the time the material being tested cooled below its closure temperature. Zircon has a very high closure temperature, is resistant to mechanical weathering and is very chemically inert. Radiometric Dating Personal tools Log in Request account.
Nuclear physics Geology Geochronology Scientific technique. Point lies on the concordia curve. Both aliquots are evaporated, 0. Prentice Hall.
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